Measuring neurochemical alterations in affected
mid-brain structures substantia nigra (SN) and putamen
in Parkinson's disease (PD) by1H
MRS has been challenging. Because recent pathological
findings indicated earlier involvement of more caudal
brainstem regions in PD before the nigrostriatal system,
we measured neurochemical profiles of the pons, as well
as the SN and putamen, in early-moderate PD by 7T1H
MRS. GABA concentration was higher in the pons (p<0.001)
and putamen (p = 0.06) in PD patients (N=11) compared to
age-matched healthy controls (N=8). Further research
will help determine how these changes relate to disease
pathogenesis and pathophysiology.

Panthotenate-kinase associated neurodegeneration is
characterized by iron accumulation in the basal ganglia.
Iron deposits were studied using T2 MR relaxometry at
1.5T, 3T and 7T in three patients and five controls. T2
values of patients decreased significantly in the globus
pallidus, increased in the putamen and nucleus caudate,
and did not differ in the thalamus and white matter; the
iron concentrations in the globus pallidus calculated
for B0=1.5T were approximately twice as high
as in controls. Measurements at different magnetic
fields suggest different ferritin loads in the basal
ganglia in patients. However, the presence of other
metalloproteins cannot be excluded.

11:18

585.

Susceptibility Mapping of
the Substantia Nigra in Parkinson patients at 7 T after one
year of diagnosis and treatment

Pathological studies have shown that the iron content in
the Substantia Nigra is increased in Parkinson patients.
It has been shown that susceptibility mapping may
indicate a higher iron concentration of the SN in vivo
in clinically diagnosed but not medicated PD patients
compared to young healthy volunteers. Here we present
results of a continuing study by calculating the
susceptibility of the SN of an age-matched control
group, and also comparing the susceptibility values of
the patients after one year of diagnosis and treatment.

Iron-containing beta-amyloid plaques may play a key role
in the development of Alzheimer’s disease (AD). To
attempt to visualize the iron component of plaques, we
performed high-resolution GRE imaging at 7.0T of AD
specimens, and derived susceptibility maps from the
phase images. Bright foci on the susceptibility maps
corresponded closely with dark foci on the GRE images,
suggesting plaques demonstrated positive magnetic
susceptibility, possibly due to microscopic iron.

11:42

587.

Spectroscopic imaging of
human medial temporal lobe epilepsy at 7T

Jullie W Pan1, Dennis D Spencer1,
R. Bradley Duckrow2, Nikolai Avdievich1,
and Hoby P Hetherington11Neurosurgery, Yale University School of
Medicine, New Haven, CT, United States,2Neurology,
Yale University School of Medicine, New Haven, CT,
United States

The presence of unilateral hippocampal atrophy in the
evaluation of medial temporal lobe epilepsy (MTLE) is
often a defining factor that if concordant with the EEG
and PET and not contraindicated from neuropsychological
data, will typically result in candidacy for surgical
resection. However, it is possible to have hippocampal
atrophy (HA) without intractable seizures particularly
in familial MTLE. We used ultra-high field MR
spectroscopic imaging at 7T to assess MTLE with patients
who are all HA positive. We studied n=12 patients who
were medically intractable and n=2 patients who were
very well controlled (seizure free for >2years on
medication).

11:54

588.

Glutamate level in the
frontal cortex decreases during young adulthood

Glutamate is the major excitatory neurotransmitter in
the central nervous system and is involved in functions
that alter with age. Using 1H-MRS (STEAM) at 7 Tesla,
glutamate was measured in the medial frontal cortex of
young adults, in which a decrease in glutamate
concentration with increasing age was found. The
decrease in glutamate concentration is in line with the
gray matter thinning in medial frontal cortex in young
adulthood. However, the change in glutamate is larger
than the gray matter change, therefore we postulate that
the observed effect is due to physiological changes
rather than anatomical changes.

12:06

589.

Effect of normal aging on
the Intra-cellular Sodium Volume Fraction in the Human
Brain: a 7T MRI in-vivo study.

Lazar Fleysher1, Niels Oesingmann2,
Ryan Brown1, Hina Jaggi1, Graham
Wiggins1, Daniel Sodickson1, and
Matilde Inglese1,31Radiology, NYU School of Medicine, New York,
New York, United States,2Siemens
Medical Solutions USA, Malvern, PA, United States,3Neurology,
NYU School of Medicine, New York, New York

Many morphologic MRI-based studies reported
age-associated volume loss of the cerebral gray and
white matters in normal aging. In this work, we report
age-related changes in the tissue sodium concentration (TSC)
in the healthy human brain. We find that TSC increases
in gray and white matter with age consistent with
cellular loss or shrinkage. The measured rate of
fractional intracellular sodium volume fraction (ISVF)
loss is found to be significantly different from the
rate of fractional tissue volume loss for both GM and WM
measured by morphologic MRI. This difference can be
explained by the micro-structural changes in GM and WM
associated with normal aging.

12:18

590.

Diffuse iron deposition in
the putamen and caudate nucleus in CADASIL: comparing phase
and magnitude images at 7 Tesla

In this study we quantified diffuse iron deposition in
cerebral autosomal dominant arteriopathy with
subcortical infarcts and leukoencephalopathy (CADASIL),
using phase and magnitude imaging on 7 Tesla MRI.
Twenty-five CADASIL patients and 15 healthy controls
were examined using high resolution T2* imaging on 7
Tesla MRI. Increased phase shift and reduced signal
intensity were found in the putamen and caudate nucleus
of CADASIL patients which is likely caused by increased
diffuse iron accumulation. In the cortex and white
matter no signs of increased iron accumulation were
found.